This invention relates to automobile electrical systems in general and more particularly to a battery booster cable having an improved type of clamp thereon.
Presently used battery booster cables generally include a spring loaded clamp made of copper or aluminum and having clamping surfaces on one end therof which are serrated. The two halves of the clamp are hinged together with the clamping surfaces which are placed around the battery post or terminal on one side of the hinge and a spring disposed on the other side to tend to bias the clamping surfaces together. Typically nonconductive covers are placed around the ends of the two halves of the clamp behind the hinge. The battery cable is attached to one of the halves at the back thereof, i.e., at the side opposite the side containing the serrations which engage the battery post or terminal.
These clamps are used on jumper-type cables which are used to conduct current from one battery to another for starting a car having a dead battery and are also used with battery chargers for recharging a battery. The clamps presently used suffer from a number of disadvantages. The most important of these is that it is quite difficult in some cases to get a good solid grip on the battery post or terminal. The clamps have a tendency to slip off causing difficulties. Furthermore, since the clamps are made completely of metal they constitute a shock hazard to the user and are relatively expensive to manufacture because of the high cost of copper or aluminum. A further disadvantage is that there is very little strain relief at the point where the cable is connected to the clamp. It is not at all uncommon for the cable to break off at this point. Generally this occurs gradually with individual wires in the cable, the cable normally being made of a plurality of twisted wires, breaking one at a time. As a result, even before the cable breaks off completely, the current carrying capability becomes substantially reduced and, in the case of jump starting, at some point insufficient current to start an automobile can no longer be carried. Current carrying capability also comes into play with regard to the type of contact which is made between the clamp and the battery post or terminal. If good contact is not made the current cannot readily pass from one to the other and difficulties arise.
Thus, there is a need for an improved battery booster cable, in particular a need for an improved clamp which will, in each case, firmly grip the battery post or terminal, which is inexpensive to manufacture, and which minimizes the possibility of the cable breaking off from the battery clamp.